A hexagonal molded rubber head forms around the rounded head of the metal bolt insert.

螺栓头部采用六边形形状，内部附有金属。

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Considering the characteristics of the mine gateway, full length recoverable cement metal bolt applicable to wall support in the mine gateway was designed and developed.

针对煤矿回采巷道的特点，设计研制出适合回采巷道煤帮支护用的杆体全长可回收水泥锚固金属锚杆。

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A full length recoverable resin metal bolt is a new bolt applied to the sidewall of the mining gateway in the mine with a good anchoring effect and recoverable advantage for reapplication.

全长可回收树脂金属锚杆是一种新型煤矿回采巷道帮用锚杆，具有锚固效果好、可回收复用的优点。

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All the other parts are purchased and the critical components like the barrel and bolt and springs are all metal.

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So the correct paint has been applied to those areas that have suffered corrosion, and a bolt with the right kind of metal has been attached to a fitting that earlier caused the "minor" flood.

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